Automatic stop mechanism for warpers



Oct. 12, 1948. J. s. SENEY I AUTOMATIC STOP MECHANISM FOR WARPERS 5Shets-Sheet l 4 Filed March 27, 1947 mm M 5% 55 NE INVENTOR.

(low/v.5.- SEA/Er .z'filzzw ATTORNEY Oct. 12, 1948.

J. S. SENEY AUTOMATIC STOP MECHANISM FOR WARPERS 5 Sheets-Shoat 2 FiledMarch 27, 1947 IN V EN TOR JOHNS. SEN: Y

A TTORNE Y "J. 5. SENEY AUTOMATIC STOP MECHANISM FOR WARPERS Oct. 12,1948.

3 Sheets-Sheet 3' Filed March 27, 1947 Oct. 12, 1948. J. 5. SENEY2,450,996

AUTOMATIC STOP MECHANISM FOR WARPERS Filed March 27, 1947- A 5Sheets-Sheet 4 I N VEN TOR.

l/OHNi-SENEY 7 BY? Z A TTO PNEY Oct. 12 1948. J. 5. SENEY 2,450,996 QAU'IOIIA'HC STOP IBOHANISII FOR WARfERS Filed March 27. 1947 5Sheets-Sheet 5 A mmvron.

; I daMvSSE/VEY ATTQAWEX Patented Oct. 12,1948

AUTOMATIC s'ror MECHANISM FOR WARPERS John S. 'Scney, Richmond, Va.,assignor to E. I. du Pont de Nemours & Company, Wilmington, 'Del., acorporation of Delaware Application March 27, 1947, Serial No. 737,585

This invention relates to warpers or the like, and more particularly toan automatic stop mechanism for stopping the warper when a thread in thewarp sheet is broken or missing.

An object of the invention is to provide a device of the above typehaving novel and improved details of construction and features ofoperation.

Another object of the invention is to provide a stop mechanism of theabove type having automatic check means for stopping the machine whenthe stop mechanism is not in proper operating condition.

Another object of the invention is to provide a stop mechanism of theabovetype including a traveling faller which traverses the thread sheetat regular intervals and is adapted to stop the warper when the spaceleft by a missing thread is encountered.

Another object of the invention is to provide a traveling faller switchof the above type with check means for checking the operating conditionof the stop circuit at intervals and for automatically stopping themachine if the stop circuit is not in proper operating condition.

Various other objects and advantages will be apparent as the nature ofthe invention is more fully disclosed.

The invention is particularly applicable to a slasher, althoughit may beapplied to any type of machine including a moving thread sheetconsisting of a plurality of spaced, parallel, longitudinal threads.Such a machine is referred to herein as a warper. In one embodiment, thestop mechanism comprises a faller switch including an arm having a headwhich is sufficiently wide to span two threads of the thread sheet butwill pass through the space left by a missing thread. The faller switchis fed transversely across the thread sheet and is held open by contactwith the various threads. However, the head is capable of passingthrough the space left by a missing thread to close the switch. Suitablecontrol mechanism is provided for stopping the machine when this occurs.

In order to permit the taller switch to pass slightly'beyond the endthreads of the thread sheet without tripping a pair of end plates areprovided adjacent the end threads which engage the taller switch head tohold the switch in open position when in contact therewith. In order tocheck the operating condition of the stop circuit. one of these platesis provided with a recess into which the head passes to close the switchwhen in registration therewith. This would normally Claims. (CI. 28-51)stop the machine. However, a check circuit is provided including acam-actuated check switch driven in synchronism with the travel of thefaller switch and arranged so that at the instant the faller switch isin registration with the recess in the end plate, the stop circuit isbroken and a check circuit is closed by the cam-actuated check switch.The check circuit is connected to stop the machine if the stop circuitis'not operating properly. Hence, the operator may be assured at alltimes when the machine is running that the thread sheet is complete andthat the stop circuit is in proper operating condition to stop themachine in the event.of failure of any of the threads of the threadsheet.

Although the novel features which are characteristic of this inventionare pointed out more particularly in the claims, the nature of theinvention will be better understood by referring to the followingdescription taken in connection with the accompanying drawings in whicha specific embodiment thereof has been set forth for purposes ofillustration.

In the drawings,

Figure l is a perspective view of a portion of a warper with a stopmechanism embodying the present invention. applied thereto;

Figure 2 is a broken front elevation of a portion of a warper showingthe thread sheet and the taller switch;

Figure 3 is a detail view of the thread comb and end plate support;

Figure 4 is an enlarged front elevation of the faller switch and endplate;

Figure 5 is a section taken on the line 55 of Figure 4;

Figure 6 is a front elevation of the faller switch;

Figure 7 is a vertical section taken on the line ll of Figure 6;

Figure 8 is a rear elevation of the faller switch;

Figure 9 is a front elevation of the check cam;

Figure 10 is a transverse section taken on the line l0l 0 of Figure 9;and

Figure 11 is a schematic circuit diagram of the stop and check circuits.

Referring to the drawings more in detail, the invention as shown isapplied to a warper carrying a plurality of threads l0 forming a threadsheet which, as shown in Figure l. are spaced by an adjustable comb ll,pass over a roller l2, and are individually rolled onto a beam I3. Thevarious details of such a warper and driving means for the thread sheetare well known in the art and only so much thereof is disclosed hereinas is necessary to an understanding of the present invention.

The "comb II is adjustably mounted for expansion or contraction inaccordance with the number of ends comprising the thread sheet. For thispurpose, the comb may be mounted on an expanding bracket I8 (Figure 3)which is adjustably supported on an oscillating arm I8 carrying bracketsI8 and I1 which support end plates is and I8. The plates I8 and I8 maybe adjusted along the arm I8 and are positioned beyond the end threadsof the thread sheet. The plates I8 and I8 are provided with adjustablepads 28 (Figure 2) bearing against a bar 2| which is mounted on theframe of the warper to insure proper clearance for the taller switch.Brackets,

28 and 21 (Figures 1, 2 and 3) are hinged to the end plates I8 and I8and carry a pair of spaced pressure bars 28 which are adapted to restagainst the front of the thread sheet for the purpose to be described.It is to be understood that the comb II and end plates I8 and I8, areoscillated in the usual manner by the arm I8 tor causing the thread tobe wound evenly on the beam I3.

In accordance with the present invention, the taller switch is mountedon a plate 38 (Figures 2 and 4-8 inclusive) which is supported andguided for travel in back oi the thread sheet I8 by means of a pair ofguide wires 8| which are held under tension in brackets 32 (Fisure 2).Springs 33 engage the plate 38 at the ends of its travel to act as shockabsorbers and to assist in reversing the movement of the plate.

Referring to Figures 48 inclusive, the plate 38, which is made ofinsulating material, is provided with an internal recess 38 in which ashaft 38 is pivoted by means of bushings 31. The shatt 38 carries an arm88 which carries at its end a head 88 which projects through a slot 8|in the plate 88 to engage the threads I8 of the thread sheet. A contactspring 82, which is attached to the plate 38 by means of a screw 83,makes electrical contact with its arm 38. A leaf spring 88, attached tothe plate 88 by screws 88-, bears against the contact spring 82 to urgethe arm 38 and head 88 outwardly against the threads I8. A hook 88. towhich a feed wire 88 is connected, is threaded into the plate 88 andmakes electrical contact with the spring 82. A screw 88, carried in theplate 38 which is mounted on plate 38 as shown in Figure 8 and also inFigure 7. bears against the spring 88 to control the tension on thetaller head 88.

The shaft 88 carries a contact arm 88 which may be provided with a capof suitable contact material, such as platinum. A contact screw 8| ismounted in the plate 88 and is provided with a contact point 88 ofsuitable contact material, such as platinum. A hook 88 tor a feed wire88 is mounted in the plate 88 and is electrically connected to thecontact screw 8| by means of a contact strip 88.

The arrangement is such that when the head 88 falls through the slot 8|.the. contact arm 88 engages the contact 88 to complete an electriccircuit from the wire 88, hook 88, contact strip 88, contact 88, arms 88and 88, spring 82 and hook 88. to the wire 88. The movement of the arm88 required to close the contact may be adjusted by means or the contactscrew 8|, the contact end of which is tapered for this purpose.

The guide wires 8| are positioned in back of the thread sheet so thatthe head 88 of the taller switch contacts the various threads I8 and is7 held inwardly thereby as the switch traverses the 4 thread sheet. Thehead 88 engages the threads I8 between the pressure bars 28 which impartthe necessary rigidity to the thread sheet tor the above purpose.

The wire 88 is wound on a drum 88 (Figures 1 and 2) which is positionedat one side at the cal groove to receive the wires 88 and 88, the endsof which are attached to the drum '88 to prevent slippage. The wire 88is broken by an insulator 68 which electrically isolates the idlerpulley 88. Electrical connections from the stop circuit to be controlledby the taller switch may be made to the idler pulley 83 and the drum 88.

A cam switch comprising a disc 18 (Figures i, 2, 9, i8, 11) is mountedon a shaft 1| which is driven by gears 12 from the motor shaft 8|. Thegears 12 have a gear ratio such that the cam disc 18 rotates throughabout 350 while the taller switch makes a complete traverse of thethread sheet. a

The disc 18 carries an adjustable cam actuator 18 which is adjustablyattached to the disc 18 by means of an adjusting screw 18. The camactuator 18 is adapted to engage a cam follower 11 attached to anactuating arm 18 of a doublethrow switch 18 carried on a supportingplate 88. The cam actuator 18 also actuates the cam tollower 88 attachedto the actuating arm 88 of the switch 88.

The disc 18 also carries a cam actuator 8| pivoted by a pin 82 to thedisc 18 and which is adapted to engage the cam follower 88 carried byactuating arm 88 of switch 88, also mounted on the plate 88. Theactuator 8| is provided with a stop pin 88 which causes the actuator 8|to actuate the cam tollower 88 when the disc 18 rotates in a clockwisedirection but permits the arm 8| to pivot about the pin 82 withoutactuating the cam follower when the disc 18 rotates in acounterclockwise direction. The switch 88 is thus actuated only when thedisc 18 rotates in a clockwise direction which corresponds to the returnmovement of the taller switch.

A plate 82 is journaled about the shaft 1| and is adapted to bearagainst an actuating arm 88 ot a single pole double-throw switch 88mounted on the plate 88. The plate 82 is held against rotation by thespring tension of the spring arm 88. A pin 81 carried by the disc 18 isadapted to engage the plate 82 as the disc 18 nears the end of its arcof rotation and alternately shifts the plate 82 onto the spring arm 88,or out of engagement therewith according to the direction of rotation ofthe disc 18.

The end plate I8 is provided with a slot I88 (Figures 4 and 8) throughwhich a yoke I8I attached to a check plate I82 passes. A plate I83 issecured to the plate I 82 by screws I88 which extend through the slotI88 and holds the check plate I82 for sliding adjustment on the endplate I8. The position ofthe check plate I82 is adjusted by means of ascrew I88 extending through a bracket I88 carried by the end plate I8and provided with a knurled adjusting knob I81. The

.check plate I82 is provided with an elongated recess I88 which isadapted to receive the head 88 of the taller switch and allow the tallerswitch to close when the head 88 registers therewith. The lateraladjustment provided by the screw I88 permits the groove I08 to be set toreceive the head 40 of the faller switch when the taller switch reachesthe end of its path of travel, across the thread sheet.

The end plate I8 is shown as carrying a similar contact plate whichengages the head 40 of the taller switch at the lefthand end of thethread across the coil I61 for improving the operation of the relay.

sheet. The contact plate is secured to the end plate I 8 in the samemanner as the plate I02 above described, and is adjustable to conformfor small variations in yarn sheet width, but does not contain a recessto permit the taller switch to b actuated.

Referring to the schematic circuit diagram of Figure 11, alternatingcurrent is supplied from -tube I23 having anodes I24 which are connectedby leads I25 to a third secondary I26 of the transformer H2. Thesecondary I26 is center-tapped and is connected to a negative lead I30.The secondary I20 is center-tapped and is connected through a lead I3I,resistor I33, choke I36, resistor I40 and lead I4I ,to the anode I42 ofa voltage regulator tube I43. A filter network comprising a resistor I34and condensers I32 and I35 is connected between the leads I30 and I3I tosmooth out the voltage fluctuations.

The cathode I44 of the voltage regulator tube I43 is connected by a leadI45 to the anode I46 of a second voltage regulator tube I41. The cathodeI48 of the tube I41 is connected by a lead I49 to a resistor I50 whichis connected to the negative lead- I30. The lead I45 is grounded at II.

A potentiometer I55 is provided with an adjustable tap connected by alead I56, resistor I51, and lead I58 to the control grid I59 of theThyratron tube H9. The lead I58 is also connected to the contact 54 ofthe faller switch. A condenser I60 is shunted across the potentiometerI55 for smoothing out the voltage fluctuation. The potentiometer I isdesigned to supply negative,

' of the double-throw microswitch 19. One contact I 0! the switch 19 isconnected by a lead I 66 to the'coil I61 0! a check relay I68, thereturn side of which is connected through a resistor I69,

return lead I10, and resistor I40, to the positive side oi the condenserI32.

The second contact I15 of the switch 19 is connected by a lead I16 tothe coil I11 of a stop relay I18, the return side of which is connectedto the return lead I10.

The negative lead I30 is connected to a normally closed contact I of theswitch 88, the arm of which is connected by a lead I8I to a normallyopen contact arm I82 of the relay I68. The arm I82 is adapted to engagea contact I83 which is connected by a lead I84 to the coil I61 01 therelay I88. A condenser I83 is shown as connected The cathode I48 of thevoltage regulator tube I 41 is also connected by a lead I88 to thenormally open contact I89 of the switch 89, the

. arm 86 of which is connected by a lead I90 to a contact arm |9I of therelay I68, which is normally .closedon a contact I92. The contact I92 isconnected to the lead I16 to the coil I11 of the stop relay I18. Thestop relay I18 is provided 'with a holding contact I98, the arm I99 ofwhich is connected by a lead 200 to the lead I49, to the cathode I48,and through the resistor I50 to the negative lead I30. A second contactarm 20I of the stop relay I18 is connected to the lead H4. The contact202 and the lead II3 are connected to leads 203 which supply power to.the warper drive or are connected to a drive control relay.

A control relay 205 is provided with a coil 206,

one side of which is connected by a lead 201 to one side of the powersupply line H0, and the other side of which is connected by a lead 208tocontact 209 of a centrifugally operated switch 2I0, the arm 2 of whichis connected by a lead M2 to the lead I I4, thence'through the switch II5 to the power supply line H0. ,The switch 2I0 is provided with acentrifugal operating mechanism, indicated at 2I4, which is connected-tobe actuated by the warper and is adapted to close the contact 209 whenthe warper is operating at full speed. A manual switch H5 is connectedacross the switch 2I0 to permit manual operation of the control relay205.

Therelay 205 is provided with a normally open contact 2I6 connected by alead 2" to one side of the power supply line "0 and cooperating with acontact arm 2I8 which is connected by a lead 2I9 to the arm 95 of thedouble-throw switch 96. The arm 95 cooperates with contacts 220 and 22Iwhich are connected respectively by leads 222 and 223 to controlwindings 224 and 225 of the motor 62. The windings 224 and 225 areconnected by a return lead 226 to the current supply Iine IIO and are soconnected that the motor 62 is reversibly operated by the selective venergization of the coils 224 and 225;

The relay 205 is also provided with a normally open contact 230 which isconnected by a lead 23I and lead 200 to the cathode lead I48. Thecontact 230 cooperates with a contact arm 232 which is connected by alead 233 to the negative lead I30.

Operation In the operation of this circuit, the manual switch H5 isfirst closed to energize the contact circuit. The warper is suppliedwith power through the lines 203 and the normally closed contact 202 ofthe stop relay I18. When the warper reaches top speed,-the.centrifuga1ly operated switch 2I0 closes, thereby energizing thecontrol relay 205 to close the contacts 2I6 and 230. The relay 205 mayalso be energized for test purposes by the manual switch 2I5 when thewarper is not running. The contact 2I6 completes the circuit through thereversing switch 96 to the control winding 224 or 225 of the motor 62and thereby causes the motor to operate and to drive the drum, 60 forfeeding the taller switch across the thread sheet in one direction orthe other depending upon the position of the reversing switch 96. Themotor also drives the disc 10 in a direction corresponding to thedirection'rof feed of the taller switch. In Figure 11,

the disc 10 and reversing switch 88 are positioned F to start the returnstroke of the taller, during 7 which the disc 10 will rotate in aclockwise direclion. The closing of the contact 230 completes thecircuit from the negative lead I30 to the cathode of the voltageregulator tube I41, thence lo the voltage regulator tube I43, andthrough the resistor I40 to the positive side of the condenser I32. Thevoltage across the voltage regulator tube I41 is connected to thepotentiometer I55 which furnishes an adjustable negative bias ior thecontrol grid of the Thyratron tube H9. The condenser I50 across thevoltage regulator tube I41 helps to stabilize the voltage across thistube. The cathode of the Thyratron tube H9 is connected to ground. Thecathode of the voltage regulator tube I43 is also grounded. Thepotentiometer I55 is adjusted to supply a negative bias to thecontrolgrid I59 of the tube II9 suited to block the tube. Upon the closing ofthe roller switch 50, the negative voltage supplied to the grid of theThyratron tube is shorted to the grounded cathode, thus dropping thenegative potential furnished by the potentiometer I55 to the samepotential as the cathode. This allows the gas in the Thyratron tube toionize and permits the flow of current from the cathode to the anode ofthat tube, and thence to the common contact arm 18 of the-switch 19.

If the faller switch has been closed with the switch in check positionat the end of its travel across the thread sheet when the head 40 of theswitch is in registration with the recess I08 in the check plate I02,the disc 10 will also be in check position with the cam follower 11 ofthe switch 19 engaged by the cam actuator 14 on the disc 10 to close thecontact I55, as shown in Figure 11. This completes the circuit from theanode lead I54, switch contact I55, line I55 to the coil I 51 of thecheck relay I58, thereby actuating that relay and closing its contactI83 to establish a holding circuit through the line I8I, and thenormally closed contact I80 of the switch 88 to the negative lead I30.The holding circuit maintains the check relay I58 energized until thecontact I80 is momentarily opened by the actuator 14 during the returnstroke of the faller switch. Actuation of the relay I58 opens thecontact I92 and breaks the energizing circuit to the coil I 11 of thestop relay I18 from the line I90, normally open contact I89 of switch 89and lead I88 to the cathode of the voltage regulator tube I41, therebypreventing the relay I18 from being actuated when the contact I89 ismomentarily closed by the actuator 8| at the beginning of the returnmovement of the disc 10. If, however, the Thyratron control circuit hadfailed to actuate the relay I58, the contact I92 would have remainedclosed and, upon the closure of the contact I89 at the beginning of thereturn movement of the disc 10, the stop relay I18 would have beenenergized through the circuit, including contacts I89 and I92.Energization of the stop relay I18 opens the contact 202 and therebyinterrupts the circuit from the supply main I I to the warper controlline 203 and stops the warper.

If the check circuit is in proper operating condition, the warperremains running and the check relay I58 remains closed until the contactI80 is opened by the actuator 14 before the taller switch and disc havereached the limit of their return stroke. The disc 10 continues torotate during the return stroke in a direction indicated as clockwise inFigure 11, until the pin 91 engages the right-hand side of the arm 82and pushes the arm 82 03 of the spring 85, thereby changing the positionof the reversing switch 98 and reversing the drive of the motor 82. Thefaller switch is now driven in its working stroke past the variousthreads of the thread sheet. During this stroke, the cam 14 is out ofengagement with the cam follower 11 and the contact I15 of the switch 19is closed. This contact sets up the circuit from the anode of theThyratron tube II9 through the line I18 to the coil I11 of the relayI18, so that the stop relay I18 is actuated in the event that the tallerswitch contact 50 closes upon reaching the space left by a missingthread and removes the negative bias from the Thyratron tube II9. Whenthe stop relay I18 is thus closed. a holding circuit i set up throughits contact I98 and line 200 from the negative lead I 80, whichmaintains the relay I18 energized until the warper has been brought torest by opening of the relay contact 202. when the warper is brought torest, the centrifugally operated switch 2I0 opens, thereby releasing therelay 205 to stop the motor 52 and open the circuit from the negativelead I30 to the voltage regulator tubes. The relay I18, however, remainsenergized through the resistor I50 and holds the warper control contact202 open until the power supply to the transformer I I2 i broken byopening the manual switch III. A suitable signal light may be provided,if desired, to indicate that the wraper has stopped operating.

During the checking stroke of the faller switch, the disc 10 rotates ina counterclockwise direction, as shown in Figure 11, until at the end ofits stroke the pin 91 engages the arm 92 and again pushes the same ontothe spring 95 to actuate the reversing switch 95. At this instant, thecam 14 engages the follower 11 to close the check circuit contact I55.During the counterclockwise rotation of the disc 10, the actuator 8Ipivots about its pin 82 on the disc 10 without actuating the switch 89.

A pilot light may also be provided to indicate when the automatic stopmechanism has been manually disconnected from the warper stop circuit soas to warn the operator that manual control 01' the warper is necessary.It will be noted that the faller switch checks each thread of the threadsheet during its check stroke and, on its return stroke, automaticallychecks the operating condition of the Thyratron tube and controlcircuits. In the event of a missing thread or of failure of the checkcircuit, the warper is immediately stopped.

Although a specific embodiment of the invention has been shown forpurposes of illustration, it is to be understood that the invention iscapable of various uses and that changes and modifications may be madetherein as will be readily apparent to a person skilled in the art. Theinvention is only to be limited in accordance with the scope of thefollowing claims.

I claim:

1. An automatic control for a warper or the like having a movingthread-sheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuit connected to be actuated by the closing of said switch 9 andadapted to stop the thread sheet driving means, means continuouslyfeeding said carriage across said thread sheet in checking and returnstrokes, and means actuated during the return strokes to test theoperative condition of said stop circuit.

2. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuit connected to be actuated by the closing of said switch andadapted to stop the thread sheet driving means, means continuouslyfeeding said carriage across said thread sheet in checking and returnstrokes, an end plate mounted beyond the last thread of said threadsheet to engage said head and having a recess to receive said head forclosing said switch at the end of said checking stroke, a cam-actuatedswitch synchronized with the carriage feed connected to break said stopcircuit and set up a test circuit before the head enters said recess, asecond cam-actuated switch actuated during the return stroke of saidcarriage and connected to complete said stop circuit, and meansresponsive to said test circuit to render said stop circuit inoperative.

3. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuit connected to be actuated by the closing of said switch andadapted to stop the thread sheet driving means, means continuouslyfeeding said carriage across said thread sheet in checking and returnstrokes, an end plate mounted beyond the last thread of said threadsheet to engage said head and having a recess to receive said head ,forclosing said switch at the end of said checking stroke, a cam-actuatedswitch synchronized with the carriage feed connected to break said stopcircuit and set up atest circuit before the head enters said recess, asecond cam-actuated switch actuated during the return stroke of saidcarriage and connected to complete said stop circuit, means responsiveto said test circuit to render said stop circuit inoperative, and athird cam-actuated switch actuated during said return stroke to clearsaid test circuit before the next checking stroke.

4. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose 10 thread to close said switch, astop circuit including an electron discharge tube connected to becontrolled by said switch, a stop relay connected to be, energized bysaid tube and adapted to stop said thread sheet driving means, meanscontinuously feeding said carriage across said thread sheet in checkingand return strokes, means closing said switch at the end of eachchecking stroke, a cam-actuated switch synchronized with the feed ofsaid carriage and connected to disconnect said tube from said stop relayand connect said tube we check relay before the closing of said switchby said last means, a test circuit connected to actuate said stop relay,a second cam-actuated switch connected to set up said test circuitduring said return stroke, and means actuated by said check relay tobreak said test circuit.

5. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuitincluding an electron discharge tube connected to be controlledby said switch, a stop relay connected to'be energized by said tube andadapted to stop said thread sheet driving means, means continuouslyfeeding said carriage across said thread sheet in checking and returnstrokes, means closing said switch at the end of each checking stroke, acam-actuated switch synchronized with the feed of said carriage andconnected to disconnect said tube from said stop relay and connect saidtube to a check relay before the closing of said switch by said lastmeans, a test circuit connected to actuate said stcp'relay, a secondcam-actuated switch connected to set up said test circuit during saidreturn stroke, means actuated by said check relay to break said testcircuit, and a third cam actu ated switch connected to deenergize saidcheck relay before the next checking stroke.

6. An automatic control for a warper or the like having a movin threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through'the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuit connected to be actuated by the closing of said switch andadapted to stop the thread sheet drivin means, an endless cableconnected to drive said carriage, a drum carrying said cable, areversible motor connected to drive said drum forcausing said carriageto traverse said thread sheet, a reversing switch for said motor, andmeans actuated at the ends of each traverse of said carriage to actuatesaid reversing switch.

7. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said 11 carriage totraverse said thread sheet with the switch normally held open by contactof said head with the threads of said sheet, means causing said head toenter the space left by a missing or loose thread to close said switch,a stop circuit connected to be actuated by the closing of said switchand adapted to stop the thread sheet driving means, an endless cableconnected to drive said carriage, a drum carrying said cable, areversible motor connected to drive said drum for causing said carriageto traverse said thread sheet, a reversing switch for said motor, andcamactuated means driven in synchronism with the feed of said carriageto actuate said reversing switch at the ends of each traverse of saidcarriage.

8. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a switch having anactuating head adapted to span two threads of said thread sheet but topass through thespace left by a missing or loose thread, a switchcarriage carrying said switch, means mounting said carriage to traversesaid thread sheet with the switch normally held open by contact of saidhead with the threads of said sheet, means causing said head to enterthe space left by a missing or loose thread to close said switch, a stopcircuit including an electron discharge tube connected to be controlledby said switch, a stop relay connected to be energized by said tube andadapted to stop the thread sheet driving means, means continuouslyfeeding said carriage across said thread sheet in checking and returnstrokes, means closing said switch at the end of each checking stroke. acam-actuated switch synchronized with the feed of said carriage andconnected to disconnect said tube from said stop relay and connect saidtube to a check relay before the closing of said switch by said lastmeans, a test circuit connected to actuate said stop relay, a secondcamactuated switch connected to set up said test circuit during saidreturn stroke, means actuated by said check relay to break said testcircuit, a third cam-actuated switch connected to deenergize said checkrelay before-the next checking stroke, and switch means responsive tothe stopping of said warper to stop said feed means and deenergize saidtube.

9. An automatic control for a warper or the like having a moving threadsheet and driving means therefor, comprising a member having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a carriagecarrying said member, means mounting said carriage to traverse saidthread sheet with the member no'rmally held retracted by contact of saidhead with the threads of said sheet, means causing said head to advanceinto the space left by a missin or loose thread, stop means connected tobe actuated by the advance of said member and adapted to stop the threadsheet driving means, means continuously feeding said carriage acrosssaid thread sheet in checking and return strokes, an end plate mountedbeyond the last thread of said thread sheet to engage said head andhaving a recess to receive said head for checking the mechanism at theend of said checkin stroke, and means adjusting the position of said endplate to conform to the width of the thread sheet.

10. An automate control for a warper or the like having a moving threadsheet and driving means therefor, comprising a contact member having anactuating head adapted to span two threads of said thread sheet but topass through the space left by a missing or loose thread, a carriagecarrying said member means mounting said carriage to traverse'saidthread sheet with the member normally held retracted by contact of saidhead with the threads of said sheet, means causing said head to advanceinto the space left by a missing or loose thread, stop means actuated bythe advance of said member and adapted to stop the thread sheet drivingmeans, means continuously feeding said carriage across said thread sheetinchecking and return strokes, and means actuated during the returnstrokes to test the operative condition of said stop means.

JOHN S. SENEY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 2,390,799\ Linsenmeyer et al. Dec. 11, 1945Certificate of Correction I Patent No. 2,450,996. October 12, 1948,

JOHN S. SEN EY It is hereby certified that errors appear in the printedspecification of the above numbered patent requiring correction asfollows:

Column 8, line 30, for wraper reed warpcr; column 12, line 21, forautomate read automatic;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Office.

Signed and sealed this 11th day of January, A. D. 1949.

THOMAS F. MURPHY, V I Assistant Commissioner of Patents.

Certificate of Correction I Patent No. 2,450,996. 7 October 12, 1948,

JOHN S. SENEY It is hereby certified that errors appear in the printedspecification of the above l numbered patent requiring correction asfollows:

Column 8, line 30, for wraper read warper; column 12, line 21, for"automatc read automatic;

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the case in thePatent Office.

Signed and sealed this 11th day of January, A. D. 1949.

THOMAS F. MURPHY, 7 Assistant Gommz'ssioner of fatal.

